In-Sewer Treatment Strategies to Control H₂S Emissions from Sewers Using a Physical Twin

Abstract

A novel scale-down Sewer Physical-Twin (SPT) system has been developed to simulate the dynamic conditions of force mains. The primary objective is to assess the presence and mitigation of hydrogen sulfide in sewer lines, targeting issues related to odor and corrosion. The key feature of this testing system lies in its adaptability to various operating conditions, such as flow velocity, retention time, and chemical dosing at different locations, making it versatile for specific on-site sewer conditions. Three SPT units, each featuring five loops, were operated for a duration of 200 days, both with and without chemical injection. The study successfully demonstrated biofilm formation, consistent sulfide production, and effective sulfide control through the addition of ferrous iron. Microbial ecology studies further unveiled a diverse range of microorganisms in both biofilm and bulk samples. This research underscores the SPT’s potential as a valuable screening tool for investigating hydrogen sulfide generation and control in sewer systems.